Italians like their coffee strong and their currencies weak. That, at least, is the conclusion one can draw from their latest round of grumbles about Europe’s single currency. But are the Italians right to moan? Is the euro overvalued?
The Economist‘s Big Mac index (see table below) suggests they have a case: the euro is overvalued by 17% against the dollar. How come? The euro is worth about $1.22 on the foreign-exchange markets. A Big Mac costs €2.92, on average, in the euro zone and $3.06 in the United States. The rate needed to equalise the burger’s price in the two regions is just $1.05. To patrons of McDonald’s, at least, the single currency is overpriced.
The Big Mac index, which The Economist has compiled since 1986, is based on the notion that a currency’s price should reflect its purchasing power. According to the late, great economist Rudiger Dornbusch, this idea can be traced back to the Salamanca school in 16th-century Spain. Since then, he wrote, the doctrine of purchasing-power parity (PPP) has been variously seen as a “truism, an empirical regularity or a grossly misleading simplification.”
Source: The Economist